G函数分析在压裂充填施工中的应用研究

The Application Of G Function In Bohai Oilfield Frac-pack Treatment

受储层特征疏松、高渗、非均质性强特点,以及压裂充填防砂井段长、射孔簇数多的井身结构等因素影响,渤海油田压裂充填施工中裂缝延伸形态复杂,加砂困难,极易发生提前脱砂,造成充填效果不理想。通过利用小型压裂测试G函数分析方法,对地层漏失类型进行诊断,快速判定压裂充填裂缝延伸形态,指导压裂充填施工泵注方案设计与调整,并最终形成一套成熟的压裂充填泵注方案优化方法。此方法可有效降低压裂充填提前脱砂比例,保证了压裂充填施工效果。文中介绍了此项技术的设计原理、现场实例和应用效果,可为其他油田压裂充填作业提供指导与借鉴意义。

Influenced by reservoir characteristic and wellbore structure,such as high permeability,strong heterogeneity,long sand control interval,many perforation clusters and so on,the fracture propagation morphologic is complex and the sand fracturing is hard to be carried out during the frac-pack treatment in Bohai Oilfield.Consequently,the screen-out happens in advance easily and the filling coefficient is lower than designed.The method of mini fracturing test G function analysis is applied to diagnose formation leakage type,determine fracture extension type,modify the fracture pumping design and finally form an optimization method of fracpack pumping.This method can greatly reduce the ratio of early screen-out and has a good effect on frac-pack construction.This paper introduces the theoretical basis,design principle and field application,which can be provided as a guide and reference on fracpack operation for other oilfields.